2012 Volume 62 Issue 2_3 Pages 79-87
Geranium robertianum L. is considered an endangered species in Japan, while it is invasive in several countries outside Japan. Recently, plants of G. robertianum have been found at several localities, none of which are original stations for G. robertianum in Japan. To determine whether the recently found plants are native Japanese plants or were naturalized from sources outside Japan, we conducted molecular phylogenetic analyses using DNA sequences of the plastid regions of the trn L intron, trnL3'-trnF and trnH-psbA intergenic spacer regions, and the nuclear internal transcribed spacer (ITS). Among 32 samples collected from 21 populations, we recognized three major groups, consisting of 1) recently found plants, 2) indigenous plants, and 3) plants from Britain. Our results suggest that recently discovered plants of G. robertianum in Japan are more likely naturalized from sources outside Japan rather than having escaped from indigenous Japanese populations. The origin of the newly found plants is not known although their origin in Britain is unlikely.
